This could have a double effect, it could boost the price and make dealing with Bitcoin easier, but it also could be a big confusion and slow adoption for a really simple reason, while we were talking for 5 years about only 21 million BTC to exist, people will be surprised about Trillions of XBT (which they don't get in the first place).
Maybe, but only a small % of the population was exposed to 21 mil number and I heard Allaire (Circle) publicly referring to 2.1 quadrillion units, which are, of course, satoshi, so some were talking about it. When i recently went to look at one house, and asked about the price, the realtor simply said 'about 7', which, based on location and my knowledge of the neighborhood, I immediately translated as '700000'. I don't know why he was so coy about it and not say 700K or seven hundred thou.
My point is use will determine, but nobody except early adopters would be reluctant because of 21 mil BTC vs 21 tril XBT, especially since some of them are already exposed to tril in GDP and budget numbers.